Collision detection is the determination of whether or not two or more entities make contact with each other during gameplay.

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What is the MTV (Minimum Translation Vector) in SAT (Seperation of axis)?

What is the MTV (Minimum Translation Vector) in SAT (Seperation of axis)? and how can i use it? Im trying to create my first game, where a ball can hit a a static brick (rectangle). Now if a ball ...
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Separation of axis theorem implementation

I have been following the this guide to implement this. My current implementation is the following: class SAT { SAT(); bool collides(Rectangle rect1, Rectangle rect2){ var axises = [ ...
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Collision detection between circle and rectangle in 2D

In a game im developing in 2D, im have one or more circles (balls) that can collide with several rectangles (bricks). Im trying to figure out a collision detection strategy, and have come up with ...
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2answers
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Pixel perfect collision detection between sprite and animated sprite

I am trying to make a collision between a sprite and an animated sprite. The animated sprite is the main character of the game. The problem I am facing is that when another sprite collides with the ...
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4answers
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Collision detection between many objects

I'm working in a 2d environment and have hundreds of objects, brute force collision checking would be out of the question, but would my method below work? For example, lets say I have a ...
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1answer
164 views

Binding BoundingSpheres to a world matrix in XNA

I made a program that loads the locations of items on the scene from a file like this: using (StreamReader sr = new StreamReader(OpenFileDialog1.FileName)) { ...
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1answer
905 views

Calculating 2D (screen) coordinates from 3D positions in XNA 4.0

I have a program that draws some items to the scene by loading their positions from a file. Now I want to place a Ray on the same location where the items are drawn. So my question is how can I ...
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2answers
392 views

Boolean checks with a single quadtree, or multiple quadtrees?

I'm currently developing a 2D sidescrolling shooter game for PC (think metroidvania but with a lot more happening at once). Using XNA. I'm utilising quadtrees for my spatial partitioning system. All ...
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2answers
305 views

How can I improve this collision detection logic?

I’m trying to make an android game and I’m having a bit of trouble getting the collision detection to work. It works sometimes but my conditions aren’t specific enough and my program gets it wrong. ...
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4answers
301 views

Big level objects collision system for 2d game

I read many variants today and get some knowledge in general, so here is a steps of mine thoughts in pictures (horrible paint.net ones). We need to develop grid system, so we check only thing near, ...
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2answers
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Basic 3D Collision detection in XNA 4.0

I have a problem with detecting collision between 2 models using BoundingSpheres in XNA 4.0. The code I'm using i very simple: private bool IsCollision(Model model1, Matrix world1, Model model2, ...
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1answer
199 views

How can I resolve collisions at different speeds, depending on the direction?

I have, for all intents and purposes, a Triangle class that objects in my scene can collide with (In actuality, the right side of a parallelogram). My collision detection and resolution code works ...
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2D Collision in Canvas - Balls Overlapping When Velocity is High

I am doing a simple experiment in canvas using Javascript in which some balls will be thrown on the screen with some initial velocity and then they will bounce on colliding with each other or with the ...
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4answers
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Checking for collisions on a 3D heightmap

I have a 3D heightmap drawn using OpenGL (which isn't important). It's represented by a 2D array of height data. To draw this I go through the array using each point as a vertex. Three vertices are ...
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2answers
226 views

Box 2D Collision Question

I am very new to Box 2D Physics world. I wanted to know how to collide 2 bodies when one is Dynamic and other is Kinematic. The whole Scenario is explained below: I have 3 balls in total. I want to ...
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3answers
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2D Tile Based Collision Detection

There are a lot of topics about this and it seems each one addresses a different problem, this topic does the same. I was looking into tile collision detection and found this where David Gouveia ...
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1answer
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XNA 2D Collision with specific tiles

I am new to game programming and to these sites for help. I am making a 2D game but I can't seem to get the collision between my character and certain tiles. I have a map filled with grass tiles and ...
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Breakout ball collision detection, bouncing against the walls

I'm currently trying to program a breakout game to distribute it as an example game for my own game engine. http://game-engine-for-java.googlecode.com/ But the problem here is that I can't get the ...
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1answer
117 views

Collision detection of player larger than clipping tile

I want to know how to check for collisions efficiently in case where the player's box is larger than a map tile. On the left is my usual case where I make 8 checks against every surrounding tile, but ...
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Ignore collisions with some objects in certain contexts

I'm making a racing game with cars in Unity. The car has a boost/nitro powerup. While boosting, I wouldn't want to be deviated when colliding with zombies, but I do want to be deviated when colliding ...
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1answer
266 views

Using 2d collision with 3d objects

I'm planning to write a fairly basic scrolling shoot 'em up, however, I have run into a query with regards to checking for collision. I plan to have a fixed top down view, where the player and ...
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1answer
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Would someone please explain Octree Collisions to me?

I've been reading everything I can find on the subject and I feel like the pieces are just about to fall into place, but I just can't quite get it. I'm making a space game, where collisions will ...
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Finding if a point is inside of a mesh (Point-in-polyhedron)

How can I find if a point (Vector3) is inside of a mesh? Would this work for both concave and convex objects? I read somewhere that if you raycast in both directions of every axis (X, -X, Y, -Y, Z, ...
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1answer
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AABB Sweeping, algorithm to solve “stacking box” problem

I'm currently working on a simple AABB collision system and after some fiddling the sweeping of a single box vs. another and the calculation of the response velocity needed to push them apart works ...
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1answer
175 views

Why does the player fall down when in between platforms? Tile based platformer

I've been working on a 2D platformer and have gotten the collision working, except for one tiny problem. My games a tile based platformer and whenever the player is in between two tiles, he falls ...
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1answer
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Question about BoundingSpheres and Ray intersections

I'm working on a XNA project (not really a game) and I'm having some trouble with picking algorithm. I have a few types of 3D models that I draw to the screen, and one of them is a switch. So I'm ...
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Complex collisions in pygame

I've seen many tutorials for simple rectangle or circle-based collision detection with pygame. But how can I do more complex collisions with arbitrary polygons? Is the only option pixel-based ...
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Collision detection - player gets stuck in platform when jumping

So I'm having some problems with my collision detection with my platformer. Take the image below as an example. When I'm running right I am unable to go through the platform, but when I hold my ...
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1answer
282 views

JigLibX collision detection only once

I try to implement collision detection in latest JiglibX using this example http://jiglibx.wikidot.com/catch-collisionevents . I choose creating callback. I try to detect collision only once. When ...
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1answer
272 views

Better way to go up/down slope based on yaw?

Alright, so I got a bit of movement code and I'm thinking I'm going to need to manually input when to go up/down a slope. All I got to work with is the slope's normal, and vector, and My current and ...
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1answer
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Collision detection with non-rectangular images

I'm creating a game and I need to detect collisions between a character and some parts of the environment. Since my character's frames are taken from a sprite sheet with a transparent background, I'm ...
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2answers
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How to detect collisions between bullet and alien

I am designing a game for Android using Surface View. When a bullet hits any point on an alien it should blow the alien up. I wrote some code to detect collisions, but my code only triggers when my ...
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2answers
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Matrix loading problems with jbullet and lwjgl

The following code does not load the matrix correctly from jbullet. //box is a RigidBody Transform trans = new Transform(); trans = box.getMotionState().getWorldTransform(trans); float[] matrix = new ...
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How to determine collision direction between two rectangles?

I am trying to figure out how to determine the direction a collision occurs between two rectangles. One rectangle does not move. The other rectangle has a velocity in any direction. When a collision ...
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3D collision detection with meshes using only raycasting?

I'm building a game using WebGL and Three.js, and so far I have a terrain with a guy walking on it. I simply cast a ray downwards to know the terrain height. How can I do this for other 3D objects, ...
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How do I determine if one polygon completely contains another?

I have 2 polygons. I know the vertex coordinates of both polygons. What's the best way to check if one is completely inside the other? For example, the algorithm should only recognize the black ...
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2answers
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Bounding volume hierarchy - linked nodes (linear model)

The scenario A chain of points: (Pi)i=0,N where Pi is linked to its direct neighbours (Pi-1 and Pi+1). The goal: perform efficient collision detection between any two, non-adjacent links: (PiPi+1) ...
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What kind of physics to choose for our arcade 3D MMO?

We're creating an action MMO using Three.js (WebGL) with an arcadish feel, and implementing physics for it has been a pain in the butt. Our game has a terrain where the character will walk on, and in ...
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1answer
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Java - 2d Array Tile Map Collision

How would I go about making certain tiles in my array collide with my player? Like say I want every number 2 in the array to collide. I am reading my array from a txt file if that matters and I am ...
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3answers
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Solving 2D Collision Detection Issues with Relative Velocities

Imagine you have a situation where two objects are moving parallel to one-another and are both within range to collide with a static wall, like this: => 20m/s => 40m/s +==========+ ...
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1answer
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Platformer Starter Kit - Collision Issues

I'm having trouble with my game that is based off the XNA Platformer starter kit. My game uses smaller tiles (16x16) then the original (32x40) which I'm thinking may be having an effect on collision ...
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Interpolation gives the appearance of collisions

I'm implementing a simple 2D platformer with a constant speed update of the game logic, but with the rendering done as fast as the machine can handle. I interpolate positions between actual game ...
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3answers
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Collision Detection Problems

So I'm making a 2D tile based game but I can't quite get the collisions working properly. I've taken the code from the Platformer Sample and implemented it into my game as seen below. One problem I'm ...
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6answers
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Should my game handle collisions in the Player object?

I'm making a 2D platform game. Right now I'm just working on making a very generic Player class. I'm wondering if it would be more efficient/better practice to have an ActionListener within the Player ...
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1answer
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Collision representation in game overworlds

I'm implementing a 2D overworld where one can walk through an area that is not tile based. I was wondering the best way to implement collisions. In the past when I've done similar things, I've used ...
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1answer
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Collision detection in multiplayer games

This a followup to my previous question: How to implement physics and AoE spells in an MMO game?. There, we concluded that all physics have to be done on the server, and that I should use cylinders ...
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2answers
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Tile map collision is not working properly

I am having problems setting collision between my sprite and the tiles. I have only done the code for colision for moving upwards but some places on the map it moves up and some places it doesn't. ...
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1answer
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Spritesheet per pixel collision XNA

So basically i'm using this: public bool IntersectPixels(Rectangle rectangleA, Color[] dataA,Rectangle rectangleB, Color[] dataB) { int top = Math.Max(rectangleA.Top, rectangleB.Top); ...
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a simple 2D rectangle collision algorithm that also determines which sides that the rectangles collide?

I initially tried out implementing rectangular intersection, which works well. However, when I have to apply the physics system, such as velocity, acceleration, and directional vectors, I would have ...
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2D Tile-based Collision Detection

I've been planning an indie game project for a while now. I'll summarise it for you so I can get right to the question. It's done entirely using the latest version of XNA through Visual Studio. ...